Healthy weight management: It’s the perennial New Year topic. When our editorial staff tackled the topic for 2012, we were excited to choose "The hormone balance plan," an in-depth look at how to “reset” your metabolism by eating (and avoiding) the right foods. After interviewing several experts, what was writer Lisa Marshall’s biggest takeaway? Eat more protein.

And this week, this approach was firmly backed up by new study published in the Journal of the American Medical Association. Over a 3-month period, study subjects overate and were deliberately inactive. Those who ate a low-protein (5 percent) diet did lose more weight—but they also stored more body fat and lost lean muscle mass. In fact, the low-protein group stored an astounding 90 percent of their calories as body fat, versus just 50 percent for the high-protein (25 percent) group. (Your body uses more energy building muscle than storing fat; we all know that, but the study results underline that this applies to our food choices, not just how much we exercise.)

Who wants to see a smaller number on the scale—if it means you’re slowing down your metabolism, gaining more fat (which has been linked to most major diseases, especially heart disease and diabetes), and losing strength that can protect you from injury (and mortality) as you age?

The study’s protein takeaway

Federal recommendations for protein (46 grams for women and 56 for men daily) may not be enough to maintain muscle mass, especially as people age (and naturally lose muscle). The study participants needed to consume at least 78 grams of protein daily to avoid losing muscle, said study author Dr. George A. Bray, MD, chief of clinical obesity and metabolism at the Pennington Biomedical Research Center, in Baton Rouge, Louisiana.